Argon

A picture of argon, but mercury is giving it the blue glow because argon is a colorless gas

Argon is one of the 7 elements in group 18

on the periodical table called noble gases. The

noble gases consist of helium, neon, argon,

krypton, xenon, radon, and ununoctium and they

are very stable. In 1785 Cavendish (an English

physicist and chemist) performed experiments

with oxygen and mixed air and he encountered

argon but only thought that he had made an error.

After nearly 100 years Lord Rayleigh found that the

nitrogen in air was denser that the nitrogen in

compounds, and there must be a heavier inert

substance in the atmosphere. Repeating the

experiments done by Cavendish with the

assistance of William Ramsey, he found an unknown

spectrum and called it Argon, which is Greek for

"inactive", due to its chemical inactivity.

Argon's appearance is as a colorless/odorless gas.

Argon is a non-metal.

Facts about Argon

Name: Argon
Symbol: Ar
Atomic Number: 18
Atomic Mass: 39.95 amu
Melting Point: -189.3 Celsius -83.85 Kelvin
Boiling Point: -186 Celsius -87.15 Kelvin
Crystal Structure: Cubic
Color: Colorless
Number of protons/electrons: 18
Number of neutrons: 22